He blasted air conditioning and music from his electric vehicle at the entrance of the Stone Arch Bridge on Tuesday, showing off its touch-screen navigation center and its roominess, unencumbered by engines. He calls it Car 2.0.

“It’s hard to imagine that electric vehicles will not completely revolutionize transportation over the next decade,” Otto said at an event that pushed the benefits of emissionless cars, such as his, sponsored by the climate-advocacy group Environment Minnesota.

Electric vehicles are becoming hot commodities nationwide. More than 190,000 electric vehicles have hit U.S. roads, and sales have spiked 500 percent in past two years, according to Environment Minnesota.

According to the Electric Power Research Institute, the state had about 2,400 electric plug-in vehicles as of 2013. Per capita, Minnesota is among the top 10 states with the highest numbers of electric vehicles in the country.

Minneapolis is making things even easier for electric-car owners: In May, the city finished installing 36 charging stalls downtown, totaling 39 stalls near downtown parking ramps. Drivers pay parking rates and for using the electricity — about $. 80 an hour. To fully charge a vehicle takes about four hours, or $3.20 in electricity, the city said.

Bruce Bisping &#x2022; bbisping@startribune.com

Otto’s Tesla Model S is among the most popular electric cars on the market.

In May, Minnesota became the first state in the country to mandate investor-owned utilities give discounts to customers who charge their vehicles in off-peak hours, which will start in 2015. These utilities must also offer an option for only renewable energy charging, said J. Drake Hamilton, science policy director for advocacy group Fresh Energy.

“This law is a win-win-win,” Hamilton said. “It’s a significant savings to customers, an extraordinary market opportunity for electric utilities and timely action for Minnesota.”

Stillwater resident John Patterson said he was inspired to purchase an electric car after seeing Otto’s Tesla at a picnic. He bought a Chevy Volt, which is the bestselling plug-in hybrid electric vehicle in the country, according to the U.S. Department of Energy.

So far, he’s satisfied, but owning an electric vehicle has required adjustments. The car can’t accelerate quickly, Patterson said, and drives best when recharging as it brakes.

The Volt switches to gas for extra energy if the temperature is under 35 degrees; in January, Patterson said he averaged 42 miles per gallon.

It gets better mileage in the summer, Patterson said, adding that he’s driven 1,200 miles on it for five gallons of gas.

“It makes it really an ideal car for the city,” he said. “It just loves traffic.”

Innovations and challenges

Tesla — perhaps the most famous name in electric cars today — is outside many people’s price range, with cars beginning at $69,900. The Chevy Volt starts at $34,185, and the Nissan Leaf starts at $28,980.

But Otto, who lives near Marine on St. Croix, said the high price is worth it for a vehicle with no fuel costs and no oil changes.

To combat the fear of running out of electricity on the road, Tesla introduced superchargers — gas station-like charging centers — for free recharges for Model S owners across the country. It takes about 20 minutes to recharge a car at 50 percent, Otto said. There are 98 supercharger stations in North America, including stations in Albert Lea and Worthington.

Otto said his Tesla can go for 250 to 300 miles before it needs a charge.

“You can actually travel right now coast to coast for free driving a Tesla,” he said.

Otto now spends $40 to charge his car in off-peak hours, vs. the $450 a month he used to spend on gas. He held up a car battery the size of a pinkie finger, 7,000 of which are under the car.

He has computerized his car to charge automatically at 8 p.m., giving him a full tank every morning. At about noon on Tuesday, Otto’s car was 81 percent charged.

Owners also noted that the tax breaks from $2,500 to $7,500, depending on battery costs and weight, can help offset prices.

“Over a 10-year window, this is actually very, very competitive with an ordinary car that is not a high-performance car,” Otto said.